We have a 2008 Cougar 5th wheel and have recently noticed a number of small and barely noticeable yellowish/brownish discoloration at points where the interior white textured ceiling panels have been fastened to the overhead rafters/joists.
I am sure that these ceiling panels have been stapled and some kind of white filler has been applied to fill in and hide the staples.
These stain marks are in a direct line and spaced fairly evenly apart - running across the ceiling from side to side. The more obvious ones are in the kitchen area but other ones are also beginning to show.
It would seem that the compound or filler that was used to hide the staples is reacting with the metal staple and producing some kind of chemical reaction which is resulting in the filler turning a light yellow/brown color. I am certain and it was confirmed by the technician that it is not a leak problem.
Upon checking with an Keystone RV dealer, I was told that this is not an uncommon problem and the stain marks might be removed by lightly rubbing it with a damp cloth and a mild detergent or cleaner.
I was also informed that the filler used becomes discolored by cooking "smoke", dust, and other airborne particles.
I am wondering if anyone else has experienced this and if so, what they have done to solve this problem. The one year warranty is, of course, expired. I havent yet contacted Keystone to see if they can offer any suggestions.
Any comments? Suggestions?